From de4f34867e7aa4b1504c28f61edb0e1c55d606a7 Mon Sep 17 00:00:00 2001
From: Corey Pauley <corey@simpleltc.com>
Date: Mon, 24 Jul 2017 10:59:54 -0500
Subject: [PATCH] Added documentation for the env_var tag in configuration
 files (#2982)

---
 source/_docs/configuration/yaml.markdown | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/source/_docs/configuration/yaml.markdown b/source/_docs/configuration/yaml.markdown
index 7ce62138fa7..07c0a8b1176 100644
--- a/source/_docs/configuration/yaml.markdown
+++ b/source/_docs/configuration/yaml.markdown
@@ -61,3 +61,20 @@ sensor:
     state_topic: sensor2/topic
 ```
 
+### {% linkable_title Using Environment Variables %}
+
+You can include values from your system's environment variables with `!env_var`.
+
+```yaml
+http:
+  api_password: !env_var PASSWORD
+```
+
+#### Default Value
+
+If an environment variable is not set, you can fallback to a default value.
+
+```yaml
+http:
+  api_password: !env_var PASSWORD default_password
+```